Currently there are substantial methane gas reserves with relatively low methane gas concentrations. Many of these reserves have methane gas concentrations from about 40 to about 80 volume percent. Currently, impurities are removed from natural gas to make pipeline quality natural gas which normally have methane concentrations of from about 95+ to about 99+ volume percent. To fuel gas turbines to make electric power, converting natural gas having methane concentrations of from about 40 to about 80 volume percent methane to pipeline quality natural gas becomes economically impractical because the conversion is capital intensive. Moreover, natural gas with methane concentrations in the range of 40 to 80 volume percent does not necessarily provide a reliable fuel source for gas turbines, especially at the low end of the latter range, to generate power with enhanced outputs of power because natural gas with such low methane concentrations will not provide a stable flame for fuel combustion without special equipment designs, catalysts and without special balancing of oxygen with other combustibles. Moreover, streams with 40 to 80 volume percent methane have the problem of NOx as a result of higher flame temperatures in the turbine.
It would be economically advantageous to utilize natural gas reserves with 40 to 80 volume percent methane and with large amounts of inert gases and purify such streams or a portion of such streams to provide a fuel for gas turbines at significantly lower cost than by producing pipeline quality natural gas for fuel for gas turbines.